1. Field of the Invention
The present invention generally relates to a container seal, and more particularly to a passive UHF omnidirectional container electronic seal.
2. Description of the Related Art
It generally adopts a mechanical container seal, a bar code seal, or an active RFID electronic container seal in the present container transportation market. Although the price of the mechanical container seal is inexpensive, it is not capable of clearing customs automatically. Opposite, the active electronic container seal is capable of offering container transportation automatically, but the cost is too expensive, the appearance is relatively big, needs to utilize battery electricity to be transmitted, and difficult to retrieve. In addition, the RFID electronic container seal of the high frequency (HF 13.56 MHZ) can't realize the long-distance transmission and has the stronger directional characteristic generally.
Therefore, the above ways for sealing the container not only increase the operation cost of enterprise, but also realize the real automation of the container clearing customs difficultly. To overcome the aforementioned problems, there is needed a new container electronic seal to overcome the disadvantage of the art. Thus, in the present invention, a novel container electronic seal is proposed.